From: A. Jesse Jiryu Davis <jesse@mongodb.com>
Date: Sat, 28 Feb 2015 18:44:27 +0000 (-0500)
Subject: Fix memory leak in Semaphore.
X-Git-Tag: v4.2.0b1~88^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F1356%2Fhead;p=thirdparty%2Ftornado.git

Fix memory leak in Semaphore.
---

diff --git a/tornado/locks.py b/tornado/locks.py
index 1367e1de8..684945a8f 100644
--- a/tornado/locks.py
+++ b/tornado/locks.py
@@ -181,7 +181,8 @@ class Semaphore(object):
     def release(self):
         """Increment the counter and wake one waiter."""
         self._value += 1
-        for waiter in self._waiters:
+        while self._waiters:
+            waiter = self._waiters.popleft()
             if not waiter.done():
                 self._value -= 1
 
diff --git a/tornado/test/locks_test.py b/tornado/test/locks_test.py
index 29d80b94f..44dbcf736 100644
--- a/tornado/test/locks_test.py
+++ b/tornado/test/locks_test.py
@@ -248,6 +248,7 @@ class SemaphoreTest(AsyncTestCase):
         sem.release()
         # Now acquire() is instant.
         self.assertTrue(sem.acquire().done())
+        self.assertEqual(0, len(sem._waiters))
 
     @gen_test
     def test_acquire_timeout(self):